Table 2.

Lipocalins in human disease.

Lipocalin	Disease
LCN1	Decreased levels are associated with Sjogren’s syndrome, laser-assisted in situ keratomileusis (LASIK)-induced dry eye, and diabetic retinopathy. Increased expression is seen in cystic fibrosis.
LCN2	Increased expression in insulin resistance, obesity, and inflammatory processes.
A1M	Increased levels in proximal tubule defects. Upregulation of A1M protects the skin from damage caused by heme and reactive oxygen species.
ApoD	Increased expression associated with altered lipid metabolism, aging, and neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease.
C8G	Deficiency of C8G is associated with rare recurrent infections of Neisseria meningitis. It controls bacterial infections by scavenging iron-containing siderophores.
PAEP	Decreased levels of PAEP are associated with first trimester abortion, while an increase is seen in gynecological malignancies, melanoma, and lung cancers.
PTGDS	Increase in attention deficit hyperactivity disorder and malignancies.
RBP4	Increased in obesity, insulin resistance, type 2 diabetes, and non-alcoholic fatty liver disease.
LCN13	Decreased expression in obesity and impact on liver lipid metabolism and fatty acid oxidation and insulin sensitivity.

Lipocalin

Disease